The study proposes to investigate the biochemical changes occurring in the secretory and plasma membrane glycoproteins in normal rats and in rats with colonic tumor induced by N-methyl-N-nitrosourea. Cell suspensions, prepared without the use of enzymes, will be examined for fate of labeled metabolites (glucose, leucine, fucose, etc.). Such cells will also be subjected to fractionation, using discontinuous Ficoll gradient centrifugation. Various glycosyltransferase activities in normal and tumorous colonic tissue will also be investigated. Glycoproteins of normal and cancerous colonic tissue will be isolated, purified, and their structural characteristics studied. Suspending medium (phosphate buffered saline containing mannitol), used for preparing single cell suspension, will be analyzed to identify potential cell aggregation promoting factors.